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perl-Coro/README

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+This module collection manages continuations in general, most often in 
+the form of cooperative threads (also called coros, or simply "coro" in
+the documentation). They are similar to kernel threads but don't (in
+general) run in parallel at the same time even on SMP machines. The
+specific flavor of thread offered by this module also guarantees you
+that it will not switch between threads unless necessary, at
+easily-identified points in your program, so locking and parallel access
+are rarely an issue, making thread programming much safer and easier than
+using other thread models.
+
+Unlike the so-called "Perl threads" (which are not actually real threads
+but only the windows process emulation (see section of same name for more
+details) ported to UNIX, and as such act as processes), Coro provides a
+full shared address space, which makes communication between threads very
+easy. And coro threads are fast, too: disabling the Windows process
+emulation code in your perl and using Coro can easily result in a two to
+four times speed increase for your programs. A parallel matrix
+multiplication benchmark (very communication-intensive) runs over 300
+times faster on a single core than perls pseudo-threads on a quad core
+using all four cores.
+
+Coro achieves that by supporting multiple running interpreters that share
+data, which is especially useful to code pseudo-parallel processes and for
+event-based programming, such as multiple HTTP-GET requests running
+concurrently. See Coro::AnyEvent to learn more on how to integrate Coro
+into an event-based environment.
+
+In this module, a thread is defined as "callchain + lexical variables +
+some package variables + C stack), that is, a thread has its own
+callchain, its own set of lexicals and its own set of perls most
+important global variables (see Coro::State for more configuration and
+background info).